It has long been known to remove sections of wood, plastic, leather, cork, bone and other materials by punching or drilling holes of a desired shape and size. Such sections have been severed by means of awls, augers, drills, saws and other cutting appliances. None of these tools, however, is capable of simply and efficiently removing a desired wedge-shaped section from a large piece of material. Augers and awls are inherently limited by their sizes and shapes, and can only sever one section at a time from any desired material. These tools generally include only one cutting surface or point, and are therefore incapable of forming a second distinct cut along a surface of material while a portion of the tool is maintained within an initial cut. Saws and drills similarly lack any blade configuration which would allow a blade portion to remain within an initial distinct cut of material while the remainder of the tool is moved to a second distinct position to cut a wedge of a desired shape and size of material.
Several tools are known in the prior art which do include a plurality of cutting surfaces to form distinct cuts in an article into which they are inserted. Steinberg, U.S. Pat. No. 2,690,750, discloses a surgical instrument for treating and removing ingrown nails. This instrument includes an annular cutting edge 18 and an annular cutting lip 20. Both cutting lip 20 and cutting edge 18, however, are located along the circumference of the same circle, and the instrument of Steinberg is therefore incapable of forming a second distinct cut along the surface of the material being worked upon without totally withdrawing the instrument in order to move it to a second distinct position.
Pekrol, U.S. Pat. No. 2,053,777, relates to a coring device for fruit which consists of a circular cutting edge 17 and an inwardly directed planar knife edge 22 located upwardly therefrom. While this device could form a plurality of cuts within the periphery of the initial cut made by element 17, it is incapable of being rotatably repositioned along a surface of a distinct material being worked on in order to form a second distinct cut at a second position.
The device of Rink, U.S. Pat. No. 3,127,939, similarly lacks any structure which would enable it to be so repositioned. Rink discloses a lawn trimmer with a lower circular cutting edge 15 and a series of sharpened vanes 14 inwardly directed and located upwardly from the bottom edge of the cutting edge. No distinct cut can be formed outside of the initially cut circle in order to sever a wedge-shaped section from the material being worked upon.
Miller, U.S. Pat. No. 1,270,040, refers to a tool for coring apples which has a plurality of cutting surfaces. Cutting edge 7 is provided at the front end of the tool together with a recessed cutting edge 8. Both of these cutting surfaces, however, appear to be located within the same cylindrical cross-section, and therefore the structural relationship between the cutting surfaces of Miller will prevent the use of the coring tool for cutting a wedge-shaped section from the material surface without having to remove the tool from the work piece and then reinserting it at a desired second position.
Finally, Hughes, U.S. Pat. No. 1,280,036, relates to a device for cutting openings or perforations in musical note sheets. This device includes a first inclined cutting edge 5, a second inclined cutting edge 6, and a third straight cutting edge 8. These three cutting edges are designed to form different portions of a slot within the note sheet to be cut. It is clear that these cutting elements could not cooperate to create a wedge-shaped portion along two distinct cuts without removing the cutting device from a workpiece to form the second cut.
None of these prior art devices is capable of severing a wedge-shaped section by forming two distinct cuts at two distinct positions without completely removing the cutting element from the surface of the material being worked upon. This inability is a result of the lack of any secondary cutting structure in the prior art devices which is recessed from an axially elongated arcuate cutting portion to form an extension of the cut made by such an arcuate portion. It is precisely this type of structure to which the present invention is directed, as the tool includes an axially recessed arcuate cutting surface as well as an outwardly directed and axially recessed planar cutting surface, both of which can be moved to a second distinct position to cut a wedge-shaped section from a workpiece while an axially elongated arcuate cutting portion is maintained within an initial distinct cut.